Scaffold



Patented Nov. 28, 1939- UNITED STATES PATENT OFFICE SCAFFOLD ApplicationFebruary 4, 1938, Serial No. 188,746

9 Claims.

This invention relates to scaffolds and, particularly, to an improvedscaffold of the portable type.

Various types of portable scaffolds have been suggested and used. Someof these have been commercially successful while others, for variousreasons, have been a failure. Usually, most of the scafiolds heretoforesuggested and used consisted of an excessive number of parts, includinga number of small parts which were apt to become lost in dismantling andtransporting them from one job to the next. Also, such scaffolds wereusually expensive in their construction and difficult to assemble, andusually required a number of men and an excessive amount of time toassemble which was also expensive; while in cases where the scaffold wassimple in design and consisted of a minimum number of parts, it wasusually unsafe for use.

It is one of the requirements of a good scaffold that the load thereonbe carried by the vertical uprights and not by the reenforcingcross-members. According to the present invention, all of the abovedisadvantages are eliminated and there is provided a scaffold having allthe necessary requirements of a good scaffold.

It is an object of the present invention to provide a scaffold which isinexpensive in construction and, at the same time, one which can beeasily and quickly assembled and dismantled.

It is another object of the invention to provide a scaffold consistingof a multiplicity of like sections, the members of which areinterchangeable with the corresponding member of any other section.

It is a further object of the invention to provide a portable scaffoldin which all of the members are made from tubular stock to obtain themaximum strength, thereby providing a scaffold which is strong andsturdy.

Various other objects and advantages of this invention will more fullyappear during the course of the following specification and will beparticularly pointed out in the appended claims.

In the accompanying drawings, We have shown, for the purpose ofillustration, one embodiment which our invention may assume in practice.

In these drawings:

Figure l is a side elevation of the improved scaffold of our invention;

Figure 2 is an elevation similar to Figure 1, looking from the otherside of the scaffold;

Figure 3 is a plan of the same;

Figure 4 is a section taken on line IV-IV of Figure 1;

Figure 5 is a vertical section through one of the leg section joints,showing the arrangement and relation of the reenforcing members on theleg;

and

Figure 6 is a view similar to Figure 5, showing a 5 modifiedconstruction of the leg joint, including means for locking the sametogether.

There is shown in the drawings, for the purpose of illustration, ascaffold of a square design consisting of three units. It will beunderstood 10 that the scaffold of the present invention can beassembled into different shapes and made to be continuous if desired, soas to provide an elongated working platform; and that any number ofunits may be used to extend the scaffold to 1| any desired height.

Each unit comprises four tubular leg sections 2 with each of thesesections having an integral extension 3 on one end thereof which issubstantially equal to the internal diameter of the a tubular sections.

There is also provided in each unit four ledger or horizontal tubularspacing members 4. Each of the horizontal members 4 has on each endthereof a vertically extending sleeve 5 which is 25 integrally connectedthereto, preferably by means of welding. The horizontal members areadapted to extend between the leg sections and each of the sleevescarried thereby is adapted to telescopically engage the extensions 3 ofthe same.

In each unit there is arranged between each of the leg sections a braceor tubular reenforcing member 6 which extends diagonally in a verticalplane between each of the leg sections. Each of the diagonal verticalbraces 6 has flattened, angularly extending apertured end portions 1.These apertured ends are adapted to telescopically engage with theextensions 3 of adjacent oppositely disposed leg sections.

There is also arranged, in a horizontal plane 4 between each of thediagonally opposed leg sections in each unit, a reenforcing tubularcrossbar or member 8. Each of these cross-bars 8 also has flattenedapertured ends 9 which are adapted to telescopically engage withextensions 3 of the 4: leg sections.

The bottom unit or base section consists of four short tubular feet orleg sections l0, each having an integral extension on one end thereofsimilar to the extension 3 on the longer leg sections 2 and a flange orpedestal II on the opposite end thereof which is 'adapted to rest uponthe ground or surface upon which the scafiold is to be erected.

There is arranged on top of the topmost unit a working platform. Thisplatform consists of four railing posts l2, four horizontal ledger orreenforcing braces I3 and, preferably, a wood floor It. If desired, atoe board l5 may be provided.

It will be understood that the connecting portions of the members aretelescopically engaged with the extensions 3 of the leg sections 2 ateach of the joints or panel points as they are sometimes called, thatis, the sleeve portions 5 of the horizontal members 4, and the flattenedapertured ends I and 9 of the diagonal braces 6 and reenforcing members8 respectively, are telescopically engaged with the extensions 3 at eachjoint between the leg sections in superimposed relation to each other sothat all the forces or stresses which are transmitted to these memberswill be transferred directly to the extensions 3 at each of the panelpoints or joints, thereby eliminating such forces being transmitteddirectly to the leg sections. Thus it will be seen by providing such aconstruction that all of the forces or stresses transmitted to themembers are transferred to the extensions 3 at substantially one pointor at least confined within a minimum distance therealong, that is, allof the vertical, horizontal and diagonal stresses meet substantially atone point at each of the joints or panel points, thereby reducing thebending or turning moment in the vicinity of the joints and on the legsections to a minimum, and this is one of the most important aspects ofthe present invention.

The scaffold of our invention may be made, if desired, with joints thatcan be locked together. That is, the units are locked together as theyare mounted one on top of the other. This can be accomplished byproviding a short threaded end portion I6 on the outer end of each ofthe extensions 3 of the leg sections 2, as shown in Figure 6, and ashort corresponding internal threaded portion H on the inside of each ofthe female ends of the leg sections 2. In assembling, all of thereenforcing members are telescopically engaged with their respectiveextensions 3 and the adjacent leg sections then screwed on to tightlyhold them in position.

It will be understood that every joint in the assembly, except the fourjoints at the base, must be composed of the members enumerated, or iffor any reason it is desired to omit any of these members from thestructure, it will be necessary to provide a filler or washer at thejoint of substantially the same thickness as the member omitted so as tomake the joint tight.

It will be seen that, as a result of this invention, there is providedan improved portable scaffold of a simple construction with reenforcingcross-bar members having flattened apertured end portions which can beeasily and quickly fabricated.

Furthermore, as a result of our invention, it will be seen that all ofthe sections and members are respectively alike and interchangeable witheach other, and this is an important advantage as it eliminates the needfor an excessive number of different sections and members, therebyproviding a scafiold which can be easily and quickly assembled anddismantled.

While we have shown and disclosed an embodiment of our invention, itwill be understood that this embodiment is merely for the purpose ofillustration and description, and that various other forms may bedevised within the scope of our invention as defined in the appendedclaims.

We claim:

1. A scaffold comprising a. plurality of legs, each of said legsincluding a series of tubular sections, each of said sections having anextension integrally arranged therewith on one end thereof substantiallyequal to its internal diameter which is adapted to telescopically engagewith the corresponding opposite end of an adjacent leg section, ahorizontal tubular member extending between each of said sections, eachof said horizontal members having a short vertically extending sleeve oneach end thereof, said vertical sleeves adapted to telescopically engagewith the extensions of said leg sections, and re- 1 enforcing tubularmembers having integral flattened apertured end portions arrangedbetween each of said leg sections with their apertured endstelescopically engaged with the extensions of said leg sections.

2. A scaffold comprising a plurality of legs, each of said legsincluding a series of tubular sections, each of said sections having anextension integrally arranged therewith on one end thereof substantiallyequal to its internal diameter which is adapted to telescopically engagewith the corresponding opposite end of an adjacent leg section, ahorizontal tubular member extending between each of said sections, eachof said horizontal members having a short vertically extending sleeveintegrally connected to each end thereof, said vertical sleeves adaptedto telescopically engage with the extensions of said leg sections, atubular member having flattened angular apertured ends positioneddiagonally in a vertical plane between each of the leg sections withtheir apertured ends engaged with the extensions of the adjacentoppositely disposed leg sections, and a horizontal reenforcing crossmember extending between each of the diagonally opposed leg sections,all of said sections and members being respectively alike andinterchangeable with each other.

3. A scaffold comprising a plurality of legs, each of said legsincluding a series of tubular sections, each of said sections having anextension integrally arranged therewith on one end thereof substantiallyequal to its internal diameter which is adapted to telescopically engagewith the corresponding opposite end of an adja cent leg section, ahorizontal tubular member extending between each of said sections, eachof said horizontal members having a short vertically extending sleeveintegrally arranged therewith on each end thereof, said vertical sleevesadapted to telescopically engage with the extensions of said legsections, a reenforcing member extending diagonally in a vertical planebetween each of said leg sections, and a tubular reenforcing crossmember having flattened apertured ends positioned substantially in ahorizontal plane between each of the diagonally opposed leg sectionswith their apertured ends engaged with the extensions of said legsections, all of said sections and members being respectively alike andinterchangeable with each other.

4. A scaffold comprising a plurality of legs, each of said legsincluding a series of tubular sections, each of said sections having anextension on one end thereof substantially equal to its internaldiameter which is adapted to telescopically engage with thecorresponding opposite end of an adjacent leg section, a horizontaltubular member extending between each of said sections, each of saidhorizontal members having a sh -rt vertically extending sleeve on eachend thereof, said vertical sleeves adapted to telescopically engage withthe extensions of said leg sections, a tubular member having flattenedangular apertured ends positioned diagonally in a vertical plane betweeneach of the leg sections with their apertured ends engaged with theextension of the adjacent oppositely disposed leg sections, a tubularreenforcing cross bar having flattened apertured ends positionedsubstantially in a horizontal plane between each of the diagonallyopposed leg-sections with their apertured ends engaged with theextensions of said leg sections. 5. A scaffold comprising a plurality oflegs, each of said legs including a series of tubular sections of equaldiameter, each of said sections havin on one end thereof an extensionsubstantially equal to its internal diameter, the outer end of saidextensions being threaded, the opposite end of each of said tubularsections having a short internal threaded portion, each of said innerthreaded portions adapted to be screwed to the threaded portions of theextension of the adjacent leg section, a horizontal tubular memberextending between each of said sections each of said horizontal membershaving a short vertically extending sleeve integrally connected to eachend thereof, said sleeves adapted telescopically to engage with theextensions of said leg sections, a tubular member having flattenedangular apertured ends positioned diagonally in a vertical plane betweeneach of the leg sections with their apertured ends engaged with theextensions of the adjacent oppositely disposed leg sections, and atubular reenforcing cross bar having flattened apertured ends arrangedbetween each of the diagonally opposed leg sections substantially in ahorizontal plane with their apertured ends engaged with the extensionsof said leg sections.

6. A scaflold having a plurality of legs, each of said legs including aseries of tubular sections substantially equal in size, each of saidsections having an extension arranged on one end thereof substantiallyequal to the internal diameter of said sections, said extensions beingsecurely attached to their respective sections and adapted totelescopically engage with the corresponding opposite end of an adjacentleg section, a threaded portion arranged on the outer end of each ofsaid extensions, said threaded portions adapted to cooperate withthreaded portions carried in the corresponding opposite ends of adjacentleg sections to securely lock the sections together, and a plurality oftubular bracing members arranged between said leg sections, each of saidtubular bracing members having means arranged on the ends thereof whichare adapted to telescopically engage with the extensions of said legsections.

7. A scafiold comprising a plurality of legs, each of said legsconsisting of a plurality of interengaged vertically aligned tubularsections, each of said sections having a reduced extension arrangedintegrally therewith on one end thereof telescopically engaging with theopposite end of an adjacent leg section, a, plurality of horizontallydisposed tubular members having a vertically disposed sleeve portionarranged integrally therewith on each end thereof with said sleeveportions telescopically engaged with said extensions between the legsections, and a plurality of diagonally disposed tubular reenforcingmembers with each having a connecting portion on each end thereof whichis also telescopically engaged with said extensions whereby the sleeveportions of the horizontally disposed members and the connectingportions of said reenforcing members are superimposed relative to eachother at each of the joints and disposed between the leg sections.

8. A scaffold including a plurality of tubular leg sections which arealike and interchangeable with each other, an extension arranged on oneend of each of said leg sections and extending outwardly from the endthereof, each of said extensions being integrally attached to the end ofits respective leg section and having an outer diameter slightly lessthan the inner diameter of said leg sections and adapted totelescopically engage with the opposite end of an adjacent leg section,a plurality of horizontally disposed tubular members which are alike andinterchangeable with each other, each of said horizontal members havinga vertically extending sleeve portion integrally arranged thereon ateach end thereof and having an outer diameter substantially equal tothat of said leg sections with each of said sleeve portions adapted totelescopically engage with the extensions between the leg sections, anda plurality of tubular reenforcing members having flattened aperturedend portions integral therewith which are also adapted to telescopicallyengage with the extensions between the le sections.

9. A scaffold comprising a plurality of tubular leg sections which arealike and interchangeable with each other, an extension arranged on oneend of each of said leg sections and extendin outwardly from the endthereof, each of said extensions being integrally attached to the end ofits respective leg section and adapted to telescopically engage with theopposite end of an adjacent leg section, a plurality of horizontally anddiagonally arranged tubular reenforcing members extending between saidleg sections with each having a connecting portion arranged on each endthereof which is adapted to telescopically engage with said extensions,said connecting portions of said tubular members at each of the jointsbeing superimposed relative to each other and disposed between thetubular leg sections, whereby the forces and stresses transmitted tosaid members are transferred to said extensions at substantially onepoint at each of said joints so as to reduce the bending moment in thevicinity thereof to a minimum.

THOMAS M. DUGAN. ANTHONY CHARLES MARTON.

